What is "equol"

n. (context biochemistry English) An isoflavandiol metabolized from daidzein by bacterial flora in the intestines.

Equol (4',7-isoflavandiol) is an isoflavandiol metabolized from daidzein, a type of isoflavone, by bacterial flora in the intestines. While endogenous estrogenic hormones such as estradiol are steroids, equol is a non-steroidal estrogen. However, only about 30-50% of people have intestinal bacteria that make equol. Equol can exist in two enantiomeric forms, (S)-equol and (R)-equol. (S)-Equol preferentially binds estrogen receptor beta.